Field
The disclosed concept relates generally to circuit interrupters, and in particular, to arc fault circuit interrupters.
Background Information
Circuit interrupters, such as for example and without limitation, circuit breakers, are typically used to protect electrical circuitry from damage due to an overcurrent condition, such as an overload condition, a short circuit, or another fault condition, such as an arc fault or a ground fault. Circuit breakers typically include separable contacts. The separable contacts may be operated either manually by way of an operator handle or automatically in response to a detected fault condition. Typically, such circuit breakers include an operating mechanism, which is designed to rapidly open the separable contacts, and a trip mechanism, such as a trip unit, which senses a number of fault conditions to trip the breaker automatically. Upon sensing a fault condition, the trip unit trips the operating mechanism to a trip state, which moves the separable contacts to their open position.
When a circuit breaker trips, it must be manually reset to restore power to the load it is protecting. For some types of loads, such as a refrigerator or freezer, leaving the load without power for an extended period of time can be costly. For example, if a circuit breaker protecting a refrigerator trips while a homeowner is on vacation, the refrigerator could go without power for an extended period of time.
In many cases, a circuit breaker tripping is not due to a persistent fault in the circuit it protects. For example, in the case of nuisance trips or transient fault issues such as, without limitation, a power surge, the circuit breaker may be safely reset and power may be restored to the protected load. However, someone must manually reset the circuit breaker to restore power to the load. In the case of a persistent fault, the fault in the circuit should be addressed before the circuit breaker is reset. Otherwise, the circuit breaker will usually trip immediately after it is reset. It would be useful to remove the need to manually reset a circuit breaker when a trip is not due to a persistent fault.
There is thus room for improvement in circuit interrupters.